Question

我尝试使用恒定模式“ beginPattern”和“ endPattern”从txt文件中提取数据，它们之间只有line1和line2中的键值是索引，然后才能在任何行中找到要提取的gettting值（key = value;）

[BEGIN_PATTERN]
    line1=abd;
    line2=ZXY;
    ...
    line43=454; 
    ...
    ...
[END_PATTERN]
[BEGIN_PATTERN]
    line1=abc;
    line2=ZXC;
    ...
    line72=847;
    ...
[END_PATTERN]
[BEGIN_PATTERN]
    line1=abe;
    line2=ZXV;
    ...
    line33=135;
    ...
[END_PATTERN]
[BEGIN_PATTERN]
    line1=abt;
    line2=ZXF;
    ...
    line54=734;
    ...
[END_PATTERN]

预期结果是：

abd,ZXY,aaa,454,ggg,ggs
abc,ZXC,mgf,847,jde,g3e
abe,ZXV,ytd,135,dfs,jhf
abt,ZXF,ytf,734,ytd,hge

我尝试使用python脚本和re.match，它只在输出文件中读取和写入值abd,ZXY到找到的第一个beginPattern和endPattern

import re

START_PATTERN = '<BEGIN'
END_PATTERN = '<BEND'

with open('DB_example.txt') as file:
    match = False
    newfile = None

    for line in file:
        if re.match(START_PATTERN, line):
            match = True
            newfile = open('my_new_file.txt', 'w')
            continue
        elif re.match(END_PATTERN, line):
            match = False
            newfile.close()
            continue
        elif match:
            #remove TAB and BreakLine
            valor=line.rstrip().replace('\t','')
            #split Key and value
            (key, val) = valor.split('=')
            if re.match('line1',key):
                match = True
                #before write into file remove ";"
                newfile.write(val.replace(';',''))
                continue
            elif re.match('line2',key):
                match:False
                newfile.write(','+val.replace(';', ''))
                continue
            elif re.match('lineXX',key):
                match:False
                newfile.write(','+val.replace(';', ''))
                continue
            elif re.match('lineYY',key):
                match:False
                newfile.write(','+val.replace(';', ''))
                continue

它不会继续第二，第三和其他模式。我的文件至少有30万个匹配项。感谢您的帮助。

Answer 1

每次打开文件，写之后都关闭文件。因此，打开文件后，每次newfile.write都会覆盖前一个。

如果要将新的val添加到文件中，请尝试在写入任何内容之前只打开一次文件，而在写入所有值之后应关闭文件。

import re

START_PATTERN = '<BEGIN'
END_PATTERN = '<BEND'
newfile = open('my_new_file.txt', 'w')
with open('DB_example.txt') as file:
    match = False
    for line in file:
        if re.match(START_PATTERN, line):
            match = True
            continue
        elif re.match(END_PATTERN, line):
            match = False
            continue
        elif match:
            #remove TAB and BreakLine
            valor=line.rstrip().replace('\t','')
            #split Key and value
            (key, val) = valor.split('=')
            if re.match('line1',key):
                match = True
                #before write into file remove ";"
                newfile.write(val.replace(';',''))
                continue
            elif re.match('line2',key):
                match:False
                newfile.write(','+val.replace(';', ''))
                continue
            elif re.match('lineXX',key):
                match:False
                newfile.write(','+val.replace(';', ''))
                continue
            elif re.match('lineYY',key):
                match:False
                newfile.write(','+val.replace(';', ''))
                continue

newfile.close()

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1 个答案: